Rotary engine valve means

ABSTRACT

This invention provides a valve system for directing charges of pressurized working fluid into the expandable chambers of a rotary engine, for operation against a pivoted power arm associated with each chamber. The valve system includes a manifold for containing a supply of pressurized working fluid, and fluid intake ports associated with each expandable engine chamber. Fluid conduit means associated with each intake port communicate with the manifold, and valve means associated with each port are adapted to open or close the conduit means in a timed sequence. Cut-off means also are provided to stop the flow of working fluid to the engine chambers after the power arm associated with each port has moved through a selected portion of its power stroke. Switching means also may be included to selectively switch the rotary engine between simple and compound modes of operation.

United States Patent 1 Hinckley et al.

[ Sept. 18, 1973 ROTARY ENGINE VALVE MEANS [75] Inventors: John N.Hinckley, Beloit; Van Tassel Stonehocker, Brookfield, both of Wis. [73]Assignee: Beloit College, 'Beloit, Wis.

[22] Filed: Apr. 1, 1971 [21] Appl. No.: 130,182

[52] US. Cl 418/249,-137/625.11, 137/625.15 [51] Int. Cl. F0lc l/00,F03c 3/00 [58] Field of Search 418/12, 249; 91/482; 137/625.11, 625.15

[56] References Cited 1 p: UNITED. STATES PATENTS 613,344 l1/1898 'White418/249 530,961 12/1894 Nielsen 91/482 832,848 10/1906 Croston 418/249 X3,233,047 12/1965 Toy.. 91/482 528,818 11/1894 Sparks 91/482 3,327,6426/1967 Budzich.. 91/482 591,165 10/1897' Greenlu 418/12 888,806 5/1908'l-lopkinsm, 418/12 Primary Examiner-Allan D. l-lerrmann Attorney-Hume,Clement, Hume & Lee

57 ABSTRACT This invention provides a valve system for directing chargesof pressurized working fluid into the expandable chambers of a rotaryengine, for operation against a pivoted powerarm associated with eachchamber. The valve system includes a manifold for containing a supply ofpressurized working fluid, and fluid intake ports associated with eachexpandable engine chamber. Fluid conduit means associated with eachintake port communicate with the manifold, and valve means associatedwith each port are adapted to open or close the conduit means in a timedsequence. Cut-off means also are provided to stop the flow of workingfluid to the 'engine chambers after the power arm associated with eachport has moved through a selected portion of its power stroke. Switchingmeans also may be included to selectively switch the rotary enginebetween simple and compound modes of operation.

7 Claims, 16 Drawing Figures PATENTED SEN 8 I973 SHEU 1 [1F 8 INVENTOR.JOHN N. HINCKLEY VAN T. STONEHOCKER.

D W. CLEMENT F. JAGER.

BY N HOW MEL PATENTED 3. 759 .640

SHEU 2 BF 3 3 D INVENTOR.

HOW Vl. CLEMENT MEL F. JAGER.

JOHN N. HINCKLEY VAN T. STONEHOCKER.

PAIENIEU EH 3.759.640

SHEEI n if 8 423 (H PC) 422 INVENTOR. JOHN M. HINCKLEY VAN T.STONEHOCKER.

HOWARD W. CLEMENT MELVIN F. JAGER.

I nsm 81912. 5 0

swears 0F 8 INVENTOR- JOHN N. HINCKLEY VAN T. STONEHOCKER HOWARD W.CLEMENT MELVIN F JAGER PATENTED 3 m a ma INVEN TOR.

' JOHN N. HINCKLEY. VAN T. STONEHOCKER.

uovmao w. CLEMENT MELVIN F. JAGER.

Omm

Omm owm own 1 no'rAnY ENGINE vALvs MEANS BACKGROUND AND GENERALDESCRIPTION This invention relates generally to valves for prime moversand more specifically relates to valve systems for use with rotaryengines of the swinging abutment type, such as described and claimed inthe co-pending application of John N. I-Iinckley, filedon Sept. 24,1969, under Ser. No. 860,684, now U.S. Pat. No. 3,684,413.

As well-known by those skilled in the art, one of the More particularly,there is a need to provide a valving system for rotary engines of thetype described in said co-pending application of John N. Hinckley. Thevalve system for such engines must be capable of use in either simple orcompound engine cycles, and further must be adaptable to permitadjustment of the admission of working fluid into the engine. The valvesystems for such engines must also function to deliver charges ofworking fluid into selected fluid chambers of the engine at timedintervals which assures a smooth and continuous flow of power to theengine output shaft. The distribution of working fluid to the enginealso must occur with maximum thermal efficiency and a minimum loss ofenergy due to friction and turbulent flow.

This invention meets the above-described needs and requirements of theart by providing valve systems for controlling the flow of pressurizedworking fluid to rotary engines. The valve systems in accordance withthis invention can operate in combination with rotary engines havingeither a simple or a compound mode of operation. The valve systems alsocan operate to admit charges of working fluid into the operatingchambers of rotary engines at variable cut-off rates, or for a fixedduration or degree of rotation of the rotor and shaft, such as at fulladmission.

Briefly, the valve system of the present invention includes a manifoldfor containing a supply of pressurized working fluid and fluid intakeports associated with each expandable chamber of the engine. Fluidconduit means place each intake port in communication with the manifold,and valve means associated with each port are adapted to open or closethe conduit means in a timed sequence. Accordingly, charges ofpressurized fluid will be sequentially admitted into the enginechambers. The valve system also includes cut-off means to stop the flowof fluid to the chambers after the associated arms move through aportion of their power strokes to control the duration of admission offluid into the engine.

EXEMPLARY EMBODIMENTS Additional features and advantages of the presentinvention will become apparent from the following description of severalpreferred embodiments thereof, taken in conjunction with theaccompanying drawings. In the drawings:

FIG. I is a partial cross-sectional end view of a simple externalcombustion engine incorporating a camoperated, adjustable poppet valvesystem in accordance with this invention;

FIG. 2 is a cross-sectional side view of the engine and valve systemillustrated in FIG. I, as viewed along the line 2-2 in FIG. I;

FIG. 3A-D are removed partial sectional views of the adjustable valvesystem for selectively controlling the admission and cut-off of theworking fluid in the engine illustrated in FIGS. ]l and 2; I

FIG. 4 is a partial cross-sectional end view of another embodiment of anexternal combustion engine incorporating an arm-actuatd adjustable slidevalve system in accordance with this invention, with the engine adaptedto be switchable between simple and compound modes of operation;

FIG. 5 is a cross-sectional side view of the switchable engine and valvesystem as viewed along the line 5-5 in FIG. d;

- FIG. 6 is aremoved end view of the fluid transfer plate incorporatedin the valve assembly illustrated in FIGS. 4 and. 5;

FIG. 7 is an end view of the transfer plate shown in FIG. 6schematically illustrating the relationship between the transfer plateand the arm-actuated valves of the present invention;

FIG. 8 is a cross-sectional side view of an engine incorporating arotational sliding valve system in accordance with this invention;

FIG. 9 is a partial cross-sectionalend view of the engine and valvesystem embodiment illustrated in FIG. 8; t

FIG. 10 is a removed and enlarged cross-sectional view of the slidingvalve plate and valve seat arrangement incorporated in the engine andvalve system illustrated in FIGS. 8 and 9;

FIG. I1 is a cross-sectional side view of an engine incorporating arotational sliding valve system which includes means to selectively varythe cut-off of the working fluid flowing into the engine;

FIG. 12 is a partial cross-sectional end view of the engine and valvesystem embodiment illustrated in FIG. 11; and

FIG. 13 is a removed and enlarged cross-sectional view of the slidingvalve plate and cut-off plate arrangement incorporated in the engine andvalve system illustrated in FIGS. 11 and I2.

EXEMPLARY EMBODIMENTS Cam-Operated Poppet Valve FIGS. 13 illustrate theadjustable cam-operated poppet valve system of the present inventionincorporated within external combustion engine unit 100. The engine is abalanced unit which is very simple in construction and is particularlyadapted for a simple mode of operation with a pressurized working fluid,

such as .carbon dioxide or superheated steam. The

structure and operation of the engine 100 are fully described in theco-pending l-Iinckley application Ser. No. 860,684 and will be referredto only briefly herein.

The engine unit 100 incorporates a double-lobe rotor 50 positionedwithin a generally cylindrical rotor housing 20 on a central drive shaft30. A key 51 or the like connects the rotor 50 to the shaft 30 in amanner which permits the rotor to float laterally within the rotorhousing 20. Six swinging abutment arms 40A-F are uniformly spaced withinthe interior of the rotor housing 2d, 60 apart, on pivot pins 41. Therotor 50 and arms 40 have approximately the same width as the rotorhousing 20.

As seen in FIG. 2, one end of the housing 20 is closed by an exhausthousing 60, and the other end is closed by a valve housing 70. Thehousings 60 and 70 support the shaft 30 on main bearings 61 and 71 andalso support the arm pivot pins 41. Machined face plates 62 and 72 sealthe adjacent ends of the rotor housing 20. Suitable means, such asdiscontinuous labyrinth sealing grooves 42 and 52 can be provided on theside portions of the arms 40 and rotor 50, respectively, to seal thearms and rotor with respect to the face plates.

As illustrated in FIG. 1, the free end of each of the arms 40A-Fincludes a bevelled portion 43 adapted for engagement with the peripheryof the rotor 50. A projection 46 on the inner surface of .each arm 40defines the point closest to the associated pivot pin 41 at which therotor 50 will engage with the arm. Further, a relief 47 in each armallows clearance for the rotor. Each arm 40 also includes a valvingportion 45A-F which extends beyond the arm pivot pins 41. 7

Further, the rotor housing 20 includes a plurality of elongate recesses22 to receive each of the arms 40 when the arms are in their outermostposition (e.g., arm 40A in FIG. 1). The rotor housing 20 also provides aplurality of arcuate recesses 25 for receiving the valve portions 45 ofthe arms 40 as the arms move inwardly toward the rotor 50. Sealingstrips 44 in the housing 20 and the arms 40 prevent pressurized workingfluid from becoming trapped in these recesses 25.

The engine 100 is also provided with means for admitting charges ofpressurized working fluid into the rotor housing 20 in the propersequence. In this regard, the valve housing 70 includes a plurality ofuniformly spaced intake ports 23. As illustrated in FIG. 1, one of theintake ports 23 is positioned in each of the arm recesses 22 closelyadjacent the free end of the associated arm 40. By this arrangement, acharge of working fluid can be admitted into the rotor housing 20through these intake ports 23 and will flow inwardly against the rotor50 and the associated arm 40, to thereby impart a torque force to therotor. The arrangement of the intake ports 23 adjacent the free end ofthe arms 40 permits the charge of working fluid to initially contact theassociated arm at a point of great leverage, so as to forcefully swingthe arm inwardly against the rotor 50.

The rotor housing 20 also includes a plurality of exhaust ports 26 whichare spaced uniformly about the housing to receive the working fluid fromthe six segments of the engine 100. As indicated in FIG. 1, an 'exhaustport 26 is positioned in each of the rotor recesses 25, directlyadjacent the valving portions 45A-F on the arms 40. Hence, the armvalving portions 45 control the opening and closing of the associatedexhaust ports 26. As illustrated by the position of the arms 40A and D,the ports 26 are closed when the arms arein their outermost positions.As similarly illustrated by the position of the arms 40C and F, theports 26 are opened to the rotor housing 20 after the associated arm 40has moved inwardly for a selected degree of rotation of the rotor 50,i.e., l to The exhaust ports 26 are thus positioned to assure that theoperation of the charges of working fluid against the rotor and theadjacent arms 40 will overlap.

The exhaust ports 26A-F can be connected to a closed fluid system if thesimple engine 100 is operated with steam as the working fluid. The spentworking fluid would then be recycled to a steam generator for reheatingand returning to the engine. On the other hand, if the working fluid iscarbon dioxide or the like, the ports 26 can be connected to a suitableexhaust manifold system (not shown) and exhausted to the atmosphere.

The periphery of the double-lobe rotor is designed to permit each of thearms 40A-F to move through a complete cycle of operation twice for eachrotor revolution. Furthermore, the rotor periphery is designed to allowthe arms 40 to move inwardly and outwardly with substantially harmonicmotion, so as to minimize inertia losses in the engine 100.

The rotor 50 defines a pair of symmetrical and diametrically opposedhigh dwell segments 54. As indicated by the arms 40A and D, the highdwell segments 54 are adapted to engage a pair of diametrically opposedarms, and to retain the arms in their outermost positions for a selecteddegree of rotor rotation. Symmetrical rotor fall segments 56 are adaptedto be engaged by a pair of opposed swinging arms 40, such as arms 40Cand 40F, as the anns are driven inwardly by the expanding working fluid.These segments 56 move the arms 40 inwardly with approximately simpleharmonic motion, so that the working fluid operating against the arm 40and the exposed portion of the rotor 50 transmits a substantial torqueforce to the shaft 30.

The double-lobe rotor 50 further includes a pair of symmetrical anddiametrically opposed low dwell segments 57. The segments 57 followthefall segments 56 on the rotor periphery and operate to slow the inwardmovement of the approaching pair of arms 40' (e.g., arms 40C and F), andmaintain the engaged arms inward in preparation for a reversal ofdirection. The fall segments 56 engage with the pairs of arms, such as40A and D, for between 55 and degrees of rotor rotation. Similarly, thelow dwell segments 57 engage the pair of arms for between approximately10 and 15 of rotor rotation. Since adjacent pairs of arms (e.g., 40A and40B) are spaced 60 apart around the rotor housing 20, the fall segments56 and dwell segments 57 provide a 10 to 15 overlap in the power strokesof adjacent arms. Thus, for 10 to 15 of rotor rotation, the charge offluid associated with the four arms 40A, C, D and F are simultaneouslytransmitting a torque force to the rotor 50 and the shaft 30.

The periphery of the double-lobe rotor 50 additionally includesdiametrically opposed and symmetrical rise segments 58. The risesegments 58 engage with the pairs of arms '40 after the dwell segments57, with the rotor 50 rotating in a clockwise direction, and return theengaged pair of arms (e.g., arms 40B and E) to their outermost positionswithin the arm recesses 22. The rise segments 58 merge into the highdwell segments 54 so that the high dwell segments will continue toretain the engaged pair of arms 40 in such outward position. The risesegments 58 are positioned so that one pair of arms, such as arms 40Cand F, does not begin a reversal of direction and move outward until thefollowing pair of arms, such as arms 40A and D, have engaged with thefall segments 56 of the rotor and have opened the associated exhaustports 26, such as the ports 26A and D. The rise segments 58 thereby alsoassure that the operation of charges against the rotor 50 and adjacentpairs of arms 40 are overlapped.

During the operationof the engine 100, each of the arms 40A-F willcomplete one cycle of operation, and

engage sequentially with a fall segment 56; a dwell segment 57; a risesegment 58; and a high dwell segment 54, as the rotor 50 rotatesthrough180 degrees. The

double-lobe rotor 50 therefore produces two complete The engine 100 inaccordance with this inventionis provided with a valving system 80 foradmitting charges of pressurized working fluid through the intake ports23 in the proper sequence, and for controlling the engine cut-off pointso as to adjust the duration of the fluid admission. As illustrated inFIGS. 2 and 3, the valve system 80 is generally cylindrical inconfiguration and is secured to the outer side of the valve housing 70by means of a mounting plate 81. The mounting plate 8 1 has a centralaperture for receiving the shaft 30, and further includes a plurality ofpassages 82 alignedwith the intake ports 23 in the adjacent housing 70.Mounting pins 83 assure the proper alignment of the housing 70, theplate 81,- and the rotor housing 20.

The valving system 80 further includes an annular valve body 84 which issecured to the mounting plate 81 so as to surround the adjacent end ofthe shaft 30. An intake passage 85 adapts the body 84 for connectionwith an external source of pressurized working carries three valve pushrods 95 which are uniformly spaced around the shaft 30 in apredetermined position with respect to the three poppet intake valvesThe rods 95 are adapted to slide radially in the member 94.

A circular hub 96 is positioned in axial alignment with the member 94adjacent the end of the shaft 30. I

As seen in FIG. 2, the hub 96 frictionally engages within a groove 97provided in the fixed cover plate 87, and thus can be rotated manuallyor automatically with respect to the member 94. The hub 96 furtherincludes an inspection cap 99 and three uniformly spaced and radiallyextended keyways for receiving the radial keys 99 on the three valvecontrol sectors 200. As shown in FIGS; SA-D, one sector 200 ispositioned radially fluid. An annular intake manifold'86 is providedinthe with a pair of opposed arms 40. Working fluid which enters any oneof the passages 88 hence will be directed simultaneously to the ports 23of the'two opposed arms 40. Since the engine 100 includes six arms40A-F, the valve body 84 includes three arcuate passages SSA-C, whichare connected, respectively, between the ports 23 associated with theopposed arms 40A and 40D; the arms 40B and E; and the arms 40C and F.

I The valve assembly 80 also includes, a plurality of poppet-type intakevalves 90 for selectively connecting the fluid passages 88A-C to theintake manifold 86. Since the engine 100 includes sixuniformly spacedarms 40 which operate in opposed pairs, it is sufficient to provide theassembly 80 with three uniformly spaced valves 90. Plugs 89 provideaccess to these valves 90 and seal the valves from the atmosphere. Theplugs 89 also support compression springs 91 which bias the valves 90inwardly toward a closed position against the valve body 84. As shown inFIGS. 3AD, the poppet valves 90 alsoinclude valve stems 92 arranged toextend inwardly into the interior of the valve body 84.

engagement with plate 81, by suitable bolts or the like, in a positionsurrounding the end of the shaft 30. The member 94 below each of theintake valves and adjacent each of the push rods 95. The circumferentialpositioning of the-sectors 2 with respect to the intake valves 90 androds hence can be controlled, within a given range,

by manually or automatically rotating the hub 96.

. The valve mechanism 80 also includes a primary admission cam 201 and acut-off control cam 202. These cams 201 and 202 are keyed to theadjacent end of the shaft 30,- and are aligned axially so that theprimaryadmission cam 201 is sequentially engageable with the three pushrods 95 and the cut-off control cam 202 is sequentially engageable withthe three sectors200. As illustrated in FIGS. 3A-D, each of the cams 201and 202 include opposed doublelobes 201A and 202A, re spectively. Thus,the cam lobes 201A and 202A will engage twice with each push rod 95 andeach valve sector 200, respectively, for each complete rotation of theshaft 30. i

Means are also provided in the valve assembly 80 to respond to theradial movement of the push rods 95 and sectors 200 and thereby controlthe operation of the intake valves 90. In this regard, a rocker leverarm 205'is positioned on a fixed pin 206 adjacent each of the valves 90.One end of each lever arm 205 is en gaged with the upper end of theadjacent push rod 95, and the other end of each am 205 is joined to acam lever 208 by means of a pivot pin 207. A spring-biased snubber rod209 is mounted in the valve body 84 directly aligned with each of thelevers 208 to prevent excess movement of the linkage formed by the arms205 and 208 during the operation of the engine 100. The free ends of thelevers 208 are positioned directly below the valve stem 92 of theadjacent intake valve 90. The levers 208 are also radially aligned withthe adjacent sliding valve sectors 200.

To operate the valve system 80, in accordance with this invention, thehub 96 is rotated to station the three sectors 200 in the desiredcircumferential position with respect to the fixed push rods 95.Sincethe relationship between the cams 201 and 202 is fixed on the shaft30, the relative positioning of the sectors 200 and rods 95 controls thetime at which the cut-off control cam 202 disengages with the sectors200 and lowers the sectors so the valve 90 can close. The adjustment ofthe hub 96 therefore adjusts the engine cutoff.

Referring in detail to FIGS. 3A-D, the operation of 'the engine 100constantly rotates the shaft 30 and the the poppet valve 90 is retainedin its closed position by the force of the compression spring 91.

However, as shown in FIG. 3C, further rotation of the shaft 30 engagesthe cam lobe 201A with the push rod 95, so that the lobe 201A drives thepush rod 95 outwardly a predetermined distance. This motion of the rod95 further causes the rocker arm 205 to rock about its fixed pivot pin206 and thereby force the connecting pin 207 radially inward. The lever208 is then rocked against the periphery of the raised sector 200 andits free end will thereby raise the valve stem 92 and open the valve 90.The valve 90 will remain in this open position as long as both the pushrod 95 and the sector 200 are engaged with the respective lobes 201A and202A on the cams 201 and 202.

The opening of the poppet valve 90 thereby brings one of the intakepassages 88A-C into fluid communication with the intake manifold ring86. A charge of pressurized working fluid, such as superheated steam orcarbon dioxide, then can be directed against a pair of arms 40 throughthe diametrically opposed intake ports 23 which are connected to thatintake passage 88.

As the shaft 30 continues to rotate, the same valving functions arerepeated sequentially, at 120 intervals, by the valve system 80 for theremaining pairs of diametrically opposed arms 40.

As illustrated in FIG. 3D, the valve 90 is closed when the continuedrotation of the shaft 30 moves the cam lobe 202A away from the sector200. The sector 200 will then move inward to relieve the forces on thelevers 205 and 208, and thereby cause the lever 208 to disengage thevalve stem 92. The poppet valve 90 then will be returned to its closedposition by the spring 91.

The valve system 80 also can be arranged to provide an advancedadmission of working fluid through the poppet valves 90, to fill thepassages 88A-C with working fluid before the associated arms begin theirinward power strokes. To accomplish the advanced valving, the cam 201 isarranged on the shaft 30 with respect to the rotor 50 so that the camlobe 201A engages with a push rod 95, and thereby begins the valveopening operation, before the associated pair of arms 40 begin theirinward power strokes against the rotor. A suitable arrangement wouldpermit the valving operation to precede the power strokes of theassociated arms by approximately 5 of rotor rotation.

The cam 202 is designed and positioned to engage the sectors 200 for aselected degree of rotation of the shaft 30 and rotor 50. In thepreferred embodiment, the cam 202 and sectors 200 cooperate so that theassociated valves 90 are opened for a sufficient duration to assure theoverlapping operation of adjacent pairs of arms. The cam 202 and sectors200 also are designed and positioned to provide the engine 100 with aselected variable cut off between full admission and zero admission. Forexample, if superheated steam is the selected working fluid, it has beenfound that an optimum design for the valve assembly 80 would cut off theadmission of steam to the expandable fluid chambers after about 25percent of the inward power strokes of the associated arms.

' As explained in co-pending application Ser. No. 860,684, the operatingcycle for the engine 100 is started by admitting charges of pressurizedworking fluid through the valve system 80 in the abovedescribed manner,so that separate fluid charges will be fed simultaneously through theports 23 to a pair of opposed arms, such as the arms 40C and 40F. Asindicated in FIG. 1, the fluid charge will operate against theassociated arms 40C and F and the rotor 50, and drive the arms inwardlyagainst the rotor fall segments 56. The pair of arms 40C and F willthereby transmit a double power stroke to the rotor 50.

As the rotor 50 continues to rotate, the valve system admits a secondcharge of working fluid into the intake ports 23 of the following pairof opposed arms, such as the arms 40A and D. The high dwell segments 54of the rotor will subsequently release this second pair of arms 40A andD and permit the arms to engage with the fall segments 56 and transmit adouble power stroke to the rotor. As described above, the fall segments56 and dwell segments 57 are arranged so that the working fluid againstthe rotor and the adjacent pairs of arms, such as arms 40A and D and 40Cand F will overlap for 10 to 15 of rotor rotation.

As further seen from FIG. 1, the inward stroke of the following pair ofarms, such as 40A and D, will open the associated exhaust ports 26 (e.g., the ports 26A and D) after the four adjacent arms have completed theabove-described overlapping operation. Then, the preceding pair of arms,such as arms 40C and F, will engage with the rise segments 58 and beginto move outward. The arms will then force the working fluid out of theengine through the exhaust ports 26 (e.g., 26A and D) which have beenopened by the following pair of arms, such as arms 40A and D. Thisabove-described cycle is repeated for each pair of arms every 60 ofrotor rotation. Due to the double-lobe configuration of the rotor 50,the cycle is repeated twice by each pair of arms for each rotorrevolution. Thus, the engine 100 will transmit twelve single powerstrokes, or six double power strokes, to the rotor 50 for each rotorrevolution.

Arm-Actuated Slide Valve FIGS. 4-7 illustrate a single engine unit 300which includes a double-lobe rotor 350 and six uniformly spaced swingingabutment arms 340A-F. The engine 300 is adapted to be switchable betweensimple and compound modes of operation, and includes a modified,arm-actuated slide valve assembly for controlling the admission ofworking fluid to the engine.

The double-lobe rotor 350 is positioned in a rotor housing 320 on acentral drive shaft 330, and the six arms 340A-F are uniformly spacedwithin the housing 320 on pivot pins 341. The rotor 350 and the arms 340are connected to the shaft 330 and the pins 341 with splines 351 or thelike which permit the rotor and arms to float laterally within thehousing 320. The arms 340 and the rotor 350 have approximately the samewidth as the rotor housing 320.

As shown in FIG. 5, the ends of the housing 320 are closed by an exhausthousing 360 and a valve housing 370. The housings 360 and 370 includemain bearings 361 and 371, respectively, to support the shaft 330, andfurther include bearing means (not shown) to pivotally support the pivotpins 341 on which the arms 340A-F rotate during the operation of theengine 300. The pins 341 extend through the housing 370 and also supportthe sliding valve assemblies 450A-F, as illustrated in FIG. 7. Keys 341Aon the shafts 341 assure that the aspin 341 in a fixed relationship.

Machined face plates 362 and 372 are defined by the interior faces ofthe housings 36d and 370, respectively, and seal the adjacent ends ofthe rotor housing 320. Furthermore, a plurality of discontinuous andunaligned labyrinth sealing grooves 352 and 342 are provided on the sideportions of the rotor 350 and arms 340, respectively, to seal the rotorand arms with re spect to these end plates 362 and 372.

As seen in FIG. 4, the arms 340A-F include bevelled portions 343 attheir free ends for engagement with the rotor 350. A projection 346 oneach arm defines the point closest to the associated pivot pin 341 atwhich the rotor 350 will engage each arm, and a relief 347 allowsclearance between each arm and the rotor during the operation of theengine. Each arm 340 further includes valving portions 345A-F extendingbeyond the pins 34l. The valving portions 345 are positioned adjacent toa plurality of exhaust ports 390A-F provided in the exhaust housing 360.Thus, the valving portions 345 will function to open and close the ports390 as the associated arms 340 move inward and outward with respect tothe rotor 350. A plurality of arcuate recesses 325 are provided in therotor housing320 adjacent the arms 340 for receiving the valvingportions 345 as the arms move inwardly toward the rotor 35d.

As further illustrated in FIG. 4, each of the arms 340A-F defines anintegral wedge-shaped horn member 348. The horns 348 are adjacent thefree end of the arms 340, and are spaced to allow the free arm ends todefine substantial contact surfaces 344. The front edge 349 of each horn348 is curved to be concentric with thepivot pin 341 and extendsoutwardly from the associated arm for a distance which exceeds thelength of the inward arm stroke. Conforming wedge-shaped recesses 328 inthe rotor housing 320 receive the horns 348 when the associated arm 340is in its outermost position. An arcuate wall 329 in the recesses 324 ispositioned to form a seal with the curved edge 349 on the arm 340 as thearm moves inwardly toward the rotor.

The recesses 328 and the rotor housing 320 thereby provide a pluralityof sealed high pressure chambers HP,,. which expand in volume as theassociated arm 340 moves inwardly toward the rotor 35th. A charge ofhigh pressure working fluid, such as superheated steam, thus can beexpanded in the chambers HP and will transmit a torque force to therotor 350 by forcing the associated arm 340 inwardly against the rotor.lFluid in-' take ports 323 are provided in the valve housing 370 toplace each of the high pressure chambers HP,,. in direct fluidcommunication with a source of high pressure fluid.

The engine unit 300 further includes a plurality of low pressurechambers LP spaced adjacent the contact surfaces 344 on the free end ofthe arms 34tlA-F. The chambers L? are adapted to receive a charge ofworking fluid, such as steam or the like, for operation against theassociated arm contact surface 344 and the periphery of the rotor 350.Low pressure intake ports 324 in the valve housing 370 are in directcommunication with each of the low pressure chambers LP By thisarrangement, working fluid can be directed into the chambers LP throughthe intake ports 324 at the desired time during the operation of theengine 300.

The periphery of the rotor 350 defines symmetrical and diametricallyopposed high dwell segments 354,

which will engage with the arms 340 to maintain the I arms outward for apredetermined degree of rotor rotation. The next portion of the rotor3561? defines symmetrical and diametrically opposed fall segments 356which will permit the arms 34% to be driven inwardly The rotor peripheryfurther includes low dwell segments 357, which engage with the pair ofarms for 10 to 15 of rotor rotation and prepare the arms for a re versaldirection. Since the adjacent arms are spaced uniformly degrees apart inthe rotor housing 32th, the fall segments 356 and dwell segments 357cause the operation of the arms to overlap by 10 to 15 of rotorrotation. During that overlapping period, two pairs of opposedarms, suchas arms 340A and D and 34M: and F, will simultaneously transmit theirpower strokes to the rotor 354).

The rotor 350 also includes a pair of symmetrical rise segments 358. Thecontinued rotation of the rotor 350 will engage apair of arms, such as343C and F, sequentially with the fall segments 356, the dwell segments357, and the rise segments 358. The segments 358 return the arms totheir outermost positions and are arranged on the rotor 35% so that theoutward movement of a pair of arms does not begin until the precedingpair of arms has started its'inward movement along the fall segments356. This arrangement assures that the preceding pair of arms, such as343A and D, will open the associated exhaust ports 3% so that theoutward arm movement will exhaust the spent working fluid from theengine 3041 through the open exhaust ports 39b.

The engine unit 3MB further includes a valving mechanism 46W foradmitting charges of high pressure working fluid to the engine and forswitching the engine betweensimple and compound modes of operation. Asillustrated in FIG. 5, the control mechanism 4th) is positione'dadjacentthe valve housing 370, and includes a transfer plate 42% and a valvebody 446). The valve body 444) defines an annular pressure storage chest4411 which is joined to an external source of working fluid, such assteam, by means of a suitable connection. The body 44@ also has sixarcuate inlet ports 443 (FIG. 5) extending through to the adjacenttransfer plate 424). The inlet ports 443 are uniformly spaced 60 degreesapart, and will function to direct fluid into the engine 300 from thepressure chest 441. Similarly, six pairs of valve ports 444 and 445 areprovided in the valve body ill, adjacent the pivot pins 341 of the arms34%, to re ceive the fluid flowing from the chest 441.

The transfer plate 424 includes passages and ports to control the flowof working fluid from the chest 441 through the ports 443, 444, and 445and to the chambers HP andlLlP of the engine 304 in this regard, thetransfer plate 420 includes six uniformly spaced L- shaped inletpassages 421 which extend in a direction concentric to the shaft 33thfor a predetermined distance and then turn radially outward. As shown inFIGS. 5 and 6, the passages 42llthereby connect the inlet ports 443 tothe adjacent valve port 444. The plate 420 further includes a series ofsix uniformly spaced L- shaped high pressure passages 422. One end ofeach passage 422 is in communication with the adjacent port 445 in thevalve body 444), and the other end of each passage terminates in a port423. As shown in W6. 5-,

the ports 423 are in axial alignment and fluid communication with theintake ports 323 in the valve housing 370, and thus lead directly intothe associated high pressure chambers HP. Thus, when the gap between theports 444 and 445 is bridged, the passages 421 and 422 are joined, andwill place the inlet ports 443 in direct fluid communication with thehigh pressure chambers HP through the ports 423.

The transfer plate 420 also includes means for transferring highpressure working fluid directly from the pressure chest 441 to the lowpressure chambers LP. The plate 420 hence has a series of six uniformlyspaced low pressure passages 424. The passages 424 are generallyL-shaped and have one end terminating in a transfer port 429 adjacentthe passage 422 and the other end terminating in a port 425. The ports425 extend through the plates 420 in axial alignment with the lowpressure inlet ports 324 in the housing 370 (FIG. 4). The passages 424thereby lead directly to the engine low pressure chambers LP. Hence, ifthe gap between the passages 422 and 424 in the plate 420 is bridged,the passages 421 and 424 will place the inlet ports 443 in direct fluidcommunication with the low pressure chambers LP. A transfer port 427 isprovided in each passage 422 adjacent the port 429 to accomplish theconnection between passages 422 and 424. Moreover, if the passages 421,422, and 424 are joined at the same time, the high pressure workingfluid in the chest 441 will simultaneously flow into both the low andhigh pressure chambers LP and HP associated with the same arms 340.Under such conditions, the engine 300 would operate as a simple engine.

The transfer plate 420 also includes six uniformly spaced transferpassages 426 to transfer the charges of working fluid from each highpressure chamber HP to the low pressure chamber LP associated with thenext adjacent arm (e.g., the next arm to engage with the rotor 350),when the engine 300 is operating in a compound mode. One end of eachtransfer passage 426 includes a transfer port 428 spaced adjacent theport 427 in the passage 422. The other end of the passage 426 ispositioned next to the low pressure passage 424 of the next adjacent arm340. These ports 427 and 428 and passages 426 and 424 can be selectivelyconnected, to join the high and low pressure chambers of adjacent arms(e.g., HP, and LP when the engine 300 is operated as a compound engine.

The valving mechanism 400 also provides a switchover assembly 430 forselectively switching the engine 300 between simple and compound modesof operation. The assembly 430 comprises a control ring 431 which ispositioned within an annular aperture in the valve housing 370. Theinner surface of the ring 431 has gear teeth which mesh with a gear 432.A control rod 433 connected to the gear 432 allows the circumferentialpositioning of the ring 431 to be shifted from outside of the valvingmechanism 400. Six arcuate valving channels 434 are secured to the ring431 by pins (not shown) so that adjustment of the ring 431correspondingly shifts the channels 434. The channels 434 are held insliding engagement with the transfer plate 420 by a wave spring 435. Thechannels 434 are positioned in radial alignment with the ports 427, 428and 429, and can be shifted to selectively connect the ports 427 toeither the adjacent transfer port 429 or the port 428. When connectingthe ports 427 and 429, the channels 434 set the engine 300 for a simplemode of operation. Alternatively, when connecting the ports 427 and 428,the channels 434 set the engine for a compound mode of operation. Thechannels 434 are also constructed to block the port 428 when connectingwith the port 429, and vice versa.

The duration of fluid admission in the illustrated engine 300 iscontrolled by a movable control ring 460. The ring 460 includes sixuniformly spaced cut-off ports 461 which are arranged in axial alignmentwith the arcuate inlet ports 443 (FIG. 5). The inside surface of thecontrol ring 460 has gear teeth which mesh with the gear 462 so thatrotation of the shaft 463 on the gear 462 will rotate the ring 460.Hence, the admission duration for the working fluid directed into theengine 300 can be adjusted by rotating the shaft 463 and the controlring 460, and thereby changing the relative positioning of the cut-offports 461 and the associated cut-off plate 451. As viewed in FIG. 7, aclockwise rotation of the control ring 460 would cause the plates 451 toclose the ports 461 earlier in the arm movement cycle, and vice versa.

As illustrated in FIGS. 5 and 7, the valving mechanism 400 also includessix uniformly spaced sliding valve assemblies 450A-F. The valveassemblies 450 are secured for rotation with the pivot pins 341 of thesix arms 340A-F by keys 341A, and slide with respect to the valve body440 when the associated arm 340 swings with respect to the rotor 350.

One end of each valve assembly 450 defines a cut-off plate 451, whichswings with the associated arm 340 and slides across the fluid inletport 461 for the arm. Thus, as illustrated by the positions of the valveassemblies 4503 and E in FIG. 7, the cut-off plates 451 allow fluid toflow into the inlet ports 461 when the associated arms 340B and E are intheir outermost positions. As further illustrated by the positions ofthe valve assemblies 450A and 450D, the cut-off plates 451 close theinlet ports 461 when the associated arms 340A and D are in theirinnermost positions. Each plate 451 thereby controls the cut off of theworking fluid into the high pressure chamber HP associated with theconnected arm 340.

The other end of each valve assembly 450 defines a pair of parallelbridge ports 452 and 453. The first bridge port 452 is adapted toconnect the adjacent ports 444 and 445, when the associated valveassembly 451 and arm 340 are in their outermost positions (see valves4508 and E and arms 340B and E). The bridge ports 452 thereby controlthe connection between the inlet passage 421 and high pressure passage422 of the preceding arm 340 (e.g., the valve 450B associated with thearm 340B controls the passages 421 and 422 for the arm 340A). The secondbridge ports 453 in the valves 450 similarly connect the low pressurepassage 424 of the preceding arm 340 to the adjacent transfer passage426 when the preceding arm and associated valve assembly 450 are intheir outermost positions (see arms 3408 and E, and valves 4503 and E).

During the operation of the engine 300, the high pressure working fluid,such as superheated steam, is continuously fed into the steam chest 441through a suitable connection. The working fluid is thereby maintainedunder pressure directly outside of the cut-off ports 461. To begin theengine operation, the control ring 460 is adjusted by the shaft 463(FIG. 5) to set the desired steam admission duration by positioning thecut-off ports 461 in a selected position with respect to thearm-actuatedcut-off plates 451. The valve assemblies 450A-F control theadmission of steam to the connected arms340A-F, respectively, andfurther control the admission into the pressure chambers of the nextpreceding arm (e.g., thevalve 450B controls admission into LP,, andHP,,, etc.). For instance, the fluid admission for the opposed arms 340AandD is controlled by the plates 451 on the connected valve assemblies450A and D. The pressurized working fluid will enter the cut-off ports461 only as long as the ports are exposed by the plates 451. However,fluid entering these ports 461 will not flow intothe associated pressurechambers LP, and D and EP and D until the following ,pair of arms 34013and E are intheir outermost positions. Under those conditions, bridgeports 452 and 453 of the following valveassemblies 45GB and E connectthe channel 421 to channel 422, and channel 424 to 'channel 426.

The mode of operation for the engine 300 is selected by adjusting theswitchover valve assembly 430. For a simple mode of operation, the rod433 is rotatedto position the six channels 434 to connect the ports 427and 429 and to block the ports 428. With a simple mode of operation,charges of working fluid will flow intothe cut-off ports 461, which areopened by the opposed valve assemblies 450C and F, and into theassociated ports 443 and channels 421. The charges then flow through theports 444 and the bridge ports 452 on the valve assemblies 450A and Dinto the ports 445 and the high pressure passages 422. The chargescontinue to flow through the ports 423 and into the high pressurechambers HP and HP associated with the arms 340A and 3400, respectively.

The fluid flowing in the high pressure channels 422 simultaneously flowsthrough the transfer ports 427 into the switchover valve channels 434(FIG. and through the transfer ports 429. Hence, the steam charge alsofills the low pressure passages 424 and will flow directly into theassociated low pressure chambers LP and LP Since the switchover channels434 block the ports 428 when the engine is set for simple operation, thefluid flowing from the passages 424 through the bridge ports 453 willnot escape from the passages 426.

Thus, when adjusted for a simplemode of operation, the valve mechanism400 directs working fluid simultaneously into the high and low pressurechambers of the pair of opposed arms 340C and 340E. The fluid will thenoperate simultaneously in both chambers against the exposed portions ofthe rotor 350 and the adjacent arms 340C and 340F and thereby impartadouble power stroke to the rotor 350.

This flow of fluid into the low and high pressure chambers HP HP LP andLP continues until the cut-off plates 451 on the valves 450C and F closethe ports 461 (FIG. 7), and the arms 340C and F approach thelow dwellsegments 357 on the rotor 350. The arms 340C and F then engage the rotorrise segments 356 and are driven outwardly, to thereby reduce the volumeof the high'pressure chambers HP and HP Simultaneously, the next pair ofarms 340A and D is forced inward by the charges of high pressure workingfluid within the chambers HP,,, HP,,, LP, and LP,;. The charge reachedthose chambers by flowing into the cutoff ports 461 opened by the valveassemblies450A and D (FIG. 7). The charge then flowed from the passages421 to the passages 422 through the bridge port 452 on .the valveassemblies 45013 and E. From the passage 422 the charge flows throughports 423 into the high pressure chambers HP, and HP and through theports 427 and'429 and the switchover channels 434 into the passages 424and the connected low pressure chambers As described above, the engine360 is timed so that the power strokes of adjacent pairs of arms 340overlap for 15 to of rotor rotation. Hence, the pairs of arms 340C and Fare engaged with the dwell segments 357.

as the arms 340A and D are moving inwardly against the rotor fallsegments 356. Thereafter, the arms 340C and F engage the rise segnents358 and are driven outwardly, and the arms 340A and D have opened theassociated exhaust ports 390A and D. The outward movement of arms 340Cand F will reduce the volume of thehigh pressure chambers HP and andforce the spent fluid charges from the passages 422 through the ports427 and 429 and switchover channels 434 into ports 390A and D.

the low pressure passage 424 and the low pressure chambers LP and LP Thespent charge will then exhaust from the engine 300 through the openedexhaust switchover channels 434 are shifted to connect the ports 4 27and 428 and block the ports 429. By this arrangement, the high pressureworking fluid will be blocked from flowing into the low pressurechambers LP through the ports 429 and passages 424. There will thereforebe no simultaneous operation of the charge in the high and low pressurechambers associated with the same arm 340.

In the compound mode of operation, the charge of working fluid flowsthrough the passages 421 and the bridge ports 452 of the valve assembly450 connected to the preceding arms (e.g., 450A and D) into the passages422 and connected high pressure chambers HP associated with a first pairof arms 341) (e.g., HP and Simultaneously, the fluid flows through theports 427 and 42% and the switchover channels 434 and fills the transferpassages 426 associated with the preceding arms 340 (e.g., arms 340A andD). However, these passages 426 are initially blocked ofi' by the inwardposition of the valve assemblies 454) of the next pair of arms (e-.g.,assemblies 4508 and E). The fluid charge will thus initially operate inthe high pressure chambers HP (e.g., HP and p) of a first pair of arms340. Then, the subsequent outward movement of the first pair of arms340, induced by the rotor rise segments 358, will force the fluid chargeinto the connected transfer passages 426. At that point in the enginecycle, the rotor dwell segments 354 hold the next pair of arms 450(e.g., 450B and E) outward so that the bridge ports 453 on theassociated valve 450 (e.g., 4508 and E) communicate with the passage426. The highpressure chambers, such as HP and p, are thereby coupled tothe low pressure chambers, such as LP, and associated with the next pairof arms 340. The charge in the high pressure chambers is therebytransferred to the coupled low pressure chambers for a second orcompounded operation against the next pair of arms 540. In the preferredarrangement, the rotor 350 and arms 340 are arranged so this transferoperation is completed while performing little or no work on the fluidcharge.

The fluid charge is exhausted from the low pressure chambers LP throughthe engine exhaust ports 390 in the manner described above for thesimple mode of operation. The cycle of operation for each pair of arms340 is completed in the above-described manner twice for each revolutionof the engine rotor 350.

Rotary Slide Valve FIGS. 8-13 illustrate two embodiments of a rotaryslide valve system in accordance with the present invention. The rotaryslide valve system illustrated in FIGS. 8-10 is incorporated within asimple external combustion engine unit, and is arranged to admit theworking fluid into the engine at a fixed cut-off, such as at fulladmission. FIGS. 11-13, the rotary slide valve system is incorporatedwithin a simple external combustion engine and is adapted to permit thecut-off of the working fluid, and thus the duration of admission offluid into the engine, to be varied.

Referring to FIGS. 8 and 9, the simple engine 500 has the same basicdesign as the engine 100 illustrated in FIGS. 1 and 2. The engine 500includes a double-lobed rotor 550 positioned within a rotor housing 520on a central drive shaft 530. A key 551 connects the rotor 550 to theshaft 530 in a free floating manner. Six swinging abutment arms 540 areuniformly spaced on pivot pins 541 within the interior of the housing520, 60 apart, as described with respect to the arms 40 in corporated inthe engine unit 100.

As seen in FIG. 8, one end of the rotor housing 520 is closed by anexhaust plate 560 and the other end is closed by a valve plate 570. Theplates 560 and 570 include main bearings 561 and 571, respectively,which support the central shaft 530. Bearings 562 and 572 also areprovided at the ends of the arm pins 541 to support the arms in theplates 560 and 570. Since the valve system in accordance with thisinvention, does not rely on arm movement to control the admissionvalving, it is not necessary for the arm pins 541 to extend through theexhaust plate 560 or the valve plate 570. The need to seal the interiorof the housing 520 at the location of the arm bearings 562 and 572 isthereby eliminated. Suitable means, such as discontinuous labyrinthsealing grooves or the like (not shown) is provided on the side portionsof the arms 540 and rotor 550 to seal the arms and rotor with respect tothe plates 560 and 570.

The basic construction and operation of the arms 540 and the rotor 550in the engine 500 are the same as described with respect to the engine100 illustrated in FIGS. 1 and 2. The charges of working fluid admittedinto the housing 520 drive the arms 540 inwardly, in the propersequence, against the periphery of the rotor 550. Each arm includes avalving portion (45A-F in FIG. I) which opens and closes associatedexhaust ports (ports 26A-F in FIG. 1) to control the exhaustion of thespent working fluid from the chamber 520. Suitable channels, such as theexhaust channel 573 illustrated in phantom lines in FIG. 8, are providedin the exhaust plate 560 to direct the spent working fluid into anexhaust manifold in a well-known manner.

The engine 500 also includes means for admitting.

charges of pressurized working fluid into the housing 520 to drive thearms 540 inward in the proper sequence. The valve plate 570 is thusprovided with six uniformly spaced intake ports 523, arranged adjacentthe free ends of each of the arms 540, such as illustrated by thesimilar ports 23 in FIG. 1. Charges of working fluid admitted into thehousing 520 through the ports 523 will be directed inwardly against therotor 550 and the free end of the associated arm 540, and will operateto impart a torque force to the rotor and the shaft 530. As describedabove with respect to the engine 100, the exhaust channels 573 arepositioned with respect to each arm 540 to assure that the operation ofthe charges of working fluid against the rotor and the adjacent arms 540will overlap. As also described with respect to the rotor 50 in theengine 100, the periphery of the double lobe rotor 550 is designed toallow the overlapping of the inward power strokes for adjacent arms 540,and to move each arm through a complete cycle of operation twice foreach rotor revolution.

The rotary slide valve system in accordance with this invention isgenerally indicated in FIGS. 8 and 9 by the reference numeral 600. Thevalve system 600 operates to admit charges of pressurized working fluidthrough the intake ports 523 in the proper sequence to operate theengine 500. In this embodiment, the system 600 is arranged to providethe engine 500 with full admission of the pressurized working fluid,that is, a charge of fluid will be directed to each arm 540 throughoutthe entire inward stroke of the arm.

As seen in'FIG. 9, the valve system 600 is generally cylindrical inconfiguration, and is secured to the outer side of the valve plate 570by means of a mounting plate 601. Plate 601 has a central opening toreceive the adjacent end of the drive shaft 530, and also includes sixports 602. One port 602 is aligned with each intake port 523 in theengine 500, so that working fluid can be admitted into the enginehousing 520 through the aligned ports 523 and 602.

The valve system 600 also includes a cylindrical valve housing 603,which is secured to the mounting plate 601 by anchor bolts 604. A coverplate 605 closes the outer end of the housing from the atmosphere. Asuitable shaft seal 606 seals the joint between the cover plate 605 andthe drive shaft 530. Valve housing 603, like the mounting plate 601, isprovided with six uniformly spaced intake ports 607 aligned with theports 602 and 523 in the mounting plate and the valve plate 570,respectively. As illustrated in FIGS. 8 and 10, each of. the housingports 607 includes a machined shear valve seat 608 which is biasedoutwardly by a spring 609 (rightward in FIG. 10). The seats 608 define ahollow shearing seal for the rotary slide valve in accordance with thisinvention, through which the working fluid can flow in a short,straight-line path from the housing 603 into the engine housing 520 bymeans of the aligned ports 607, 602, and 523. The same valve seat can beused in the engine 300 to maintain a seal between the valve ports 444and 445 and the bridge ports 452 and 453, illustrated in FIG. 5.

The valve system 600 further includes a rotatable annular valve plate610, adapted to rotate with the engine shaft 530. As shown in FIG. 8,the valve plate 610 is spaced closely adjacent the ports 607 provided inthe housing 603, and is arranged to be in constant sliding contact withthe shear valve seats 608. The bias of the seat springs 609 maintainsthe sliding contact as the plate 610 continuously rotates with the shaft530 during the operation of the engine 500.

As shown in FIG; 9, the valve plate 610 includes concentric admissionslots 612A and 6128 having a predetermined arcuate length. The slots612A, B are arranged in axial alignment withthe valve seats 608 and theports 607, 602, and 523. Thus, during a portion of the rotation of theplate 610 the slots 612A and B will be aligned with each of the seats608, and will place the ports 607, 602, and 523 and the engine housing520 in open fluid communication with the interior of the valve housing603.

The size and number of slots 612A, B in the plate 610 is a function ofthe number of arms 540 and the design of the rotor 550 provided in theengine 500. in the illustrated embodiment, wherein the engine 500includes six uniformly spaced arms 540 and a double-lobed rotor 550, theslots 612A and B in the valve plate 610 are identical and diametricallyopposed. The arcuate length of each admission slot, along the plateangle alpha indicated in FIG. 9, and the width of the aligned ports 607,are selected to provide the desired admission and cut-off for theworking fluid which will pass through the slots during the operation ofthe engine 500. Since the illustrated engine 500 is adapted for fulladmission, the length of the slots 612A and B, and the width of theports 607, are selected to direct working fluid from the valve housing603 into the rotor housing 520 during the complete inward power strokefor each arm 540. Since the arms 540 are uniformly spaced 60f apart, theslot length and port width combine to admit fluid into the rotor housing520 through each port 607 for at least 60 of rotor rotation. In theillustrated embodiment, theslots 612A and B and the ports 607 are alsodesigned to provide an overlap in the admission of the charges ofworking fluid into two adjacent expansion chambers. As described withrespect to the engine 100, an overlap in arm movement in the range of ofrotor rotation will assure smooth operation of the engine 500. Further,the admission slots 612A and B and ports 607 are selected to admitworking fluid into each port 523 for about five degrees of rotorrotation in advance of inward movement of the associated arm 540. Thisadvance admission brings the fluid in the ports 523, 602, and 607 up tothe desired inlet pressure before arm movement begins. Hence, for fulladmission, the effective arcuate length of the admission slots 612A andB (the angle alpha) and the aligned ports 607 are preferably about 80 ofrotor rotation.

The valve system 600 also includes driving means to rotate the slidingvalve plate 610 in unison with the drive shaft 530 of the engine 500. Inthis regard, a timing hub 620 is keyed to the shaft 530, by a suitablekey 621, to rotate with the shaft 530. A drive hub 630 is connected tothe timing Mb 620 by a set of adjusting screws 631. As illustrated inFIG. 9, the screws 631 are positioned within slots 632 on the drivinghub 630, so that the circumferential positioning of the driving hub 630can be adjusted with respect to the timing hub 620.

The slots 632 thereby allow the timing of the admission of the workingfluid into the engine 500 to be set within a selected range.

A plurality of uniformly spaced drive pins 633 rigidly v join thedriving hub 630 to the valve plate 610. Thus,

the rotational force imparted to the timing hub 620 by the shaft 530through the keys 621i is transmitted by the adjusting screws 631 to thedriving hub 630, and is, in

turn, transmitted to thevalve plate 610 through the driving pins 633. Aplurality of compression springs 634 are also spaced uniformly aroundthe periphery of the, driving hub 630, to continuously bias the rotatingvalve plate 610 inwardly (leftward in FIG. 0) against the valve seats608.

The cover plate 5 and the seal606 enclose the outer end of the valvehousing 603. A shaft seal 635 is provided on the mounting plate 601 toseal the inner end of the valve housing 603 in the same manner. Thrustwashers 636 are provided adjacent both ends of the timing hub 620mabsorb any axial thrust created by the movement of the components of thesystem 600 during the operation of the engine 500. The housing 603 alsoincludes an admission port 640 which can be connected to a suitablesupply of working fluid and which operates to fill the housing 603 withworking fluid during the operation of theengine.

To begin the operation of the engine 500, working fluid, such assuperheated steam or carbon dioxide, is fed into the interior of thevalve housing 603 through the admission port 640. As indicated in FIG.9, the slots 612A and 6128 and ports 607 assure that at least a pair ofdiametrically opposed ports 523, 602, 607 will be exposed to theinterior of the valve housing 603 at any time, regardless of where therotation of the valve plate 610 was stopped during the previousoperation of the engine 500. Thus, charges of pressurized working fluidwill flow from housing 603 into the rotor housing 520 through a pair ofthe ports 523 and-act upon the rotor 550 and the associated pair ofopposed arms 540. The pair of arms 540 will thereby be forced inwardlyand transmita torque force to the rotor 550 and shaft 530. The alignedports 607, 602, 523 define a straight-line path for the charges ofworking fluid, and thereby allow the charges to flow into the rotorhousing 520 with minimum loss of energy due to friction and flowturbulence.

During the operation of the sliding valve system 600, the compressionsprings 634 constantly urge the rotating valve plate 610 axially inward(to the left in FIG. 8)

against the shear valve seats 608. The springs 609 simultaneously urgethe seats 608 outward (to the right in FIG. 8) into engagement with therotating plate 610. The springs 634 and 609 thus assure initial andcontinuous sealing contact between the sliding valve plate 610 and thevalve seats 600. The pressure of the working fluid in the valve housing603 also acts against the rotating plate 610 in a manner which assiststhis sealing action. As shown in FIG. 10, the valve seats 608 caninclude 0 rings to seal the seat to the housing.

As the pressurized working fluid continues to exert a torque forceagainst the rotor 550, the rotor and the shaft 530 rotate in a clockwisedirection as viewed in FIG. 1, or a counterclockwise direction as viewedin FIG. 0. The movement of the shaft 530 rotates the timing hub 620, thedrive hub 630, and the valve plate 610 through the same angularmovement, in the same direction. The admission slots 612A and 61213 arethereby successively rotated into axial alignment with diametricallyopposed ports 607 602, 523 for a selected degree of rotor rotation. Thevalve plate 610 thus operates to control the successive admission ofcharges of working fluid into the engine 500. Since the engine 500 isadapted for full admission, the slots 612A and B admit working fluidinto the ports 523 throughout the entire inward power'stroke of theassociated arms 540. As described above, the total duration of theadmission is preferably about 80 of rotor rotation, to allow for aboutadvance admission, before any arm movement, and about of overlap in theoperation of adjacent arms 540. The torque force transmitted to therotor 550 and shaft 530 will thereby be continuous and substantiallyuniform.

FIGS. 11 through 13 illustrate a further embodiment of this inventionwherein a modified sliding valve system 700 is adapted to permitmanualadjustment of the cut-off for the admission of the working fluidinto the engine 500A. The engine 500A is essentially the same as theengine 500, described above with respect to FIGS. 8 through 10, andhence like components have been given the same reference numerals inFIGS. 11 through 13. The modified sliding valve system 700 is secured tothe engine 500A adjacent the valve plate 570 by means of a plurality ofuniformly spaced anchor bolts 70].

Referring to FIGS. 11-13 in more detail, the slide valve system 700includes a generally cylindrical valve body 703 which defines aninterior fluid chamber or steam chest. A central aperture 702 in thebody 703 receives the adjacent end of the engine shaft 530A. A series ofpositioning screws 704 assure that the valve body 703 is mounted on thevalve plate 570 of the engine 500A in the proper position.

The valve body 703 includes a series of uniforml spaced channels orports which allow working fluid to flow from the interior of the valvebody into each intake port 523 of the engine 500A. In this embodimentthe channels are formed by a plurality of ports 705A and 705B. The ports705A and B are staggered around the valve body 703 in a uniformly spacedrelationship. The inner ends of the ports 705A and B (the left end inFIG. 11) are aligned with the adjacent intake port 523. The ports 705Aand B extend through the valve body 703 in divergent directions so thatthe outer ends of the channels 705A are spaced radially in the valvebody from the alternate ports 705B. In the illustrated embodiment, theports 705A are spaced radially outward with respect to the ports 705B.Each port 705A and B thus will permit working fluid to be admitted fromthe interior of the valve body 703 through the intake ports 523 and intothe engine housing 520. The staggered and radially spaced arrangementfor the ports 705A and B allows the duration of admission of the workingfluid to be adjusted.

The valve system 700 also includes a rotatable sliding valve plate 710.The plate 710 is annular to provide a central opening for receiving theadjacent end of the shaft 530A. Furthermore, the plate 710 includes twosets of arcuate admission slots 712A and B and 714A and B which arepositioned in diametrically opposed relationship. The plate 710 isarranged inside the valve body 703 coaxially with the shaft 530A so thatthe admission slots 712A and 714A are axially aligned with the outerends of the ports 705A. Similarly, the admission slots 7128 and 714Baligned with the outer ends of the ports 7058. Thus, the working fluidcan flow from the interior of the valve body 703 into the channels 705Athrough the admission slots 712A and 714A and into the channels 705Bthrough the admission slots 7128 and 714B.

Means are provided in the valve system 700 to rotate the slotted valveplate 710 in unison with the shaft 530A. In this regard, a timing hub720 is secured to one end of the shaft 530A by a suitable key 721. Adriving hub 730 is joined for rotation with the timing hub 720 by meansof adjusting screws 731. As seen in FIG. 12, the screws 731 are receivedby the driving hub 730 in slots 732 so that the timing of the valvesystem can be set by adjusting the relative positioning of the hubs 720and 730. A series of uniformly spaced driving pins 733 join the drivinghub 730 to the valve plate 710, so that the plate and hub will rotate inunison. The pins 733 are further arranged to allow the plate 710 to moveaxially with respect to hub 730 to facilitate sealing of the valvesystem 700 during the operation of the engine 500A.

The valve system 700 also includes a cut-off plate 740 to vary thecut-off duration for the charges of working fluid admitted into theengine 500A. The cutofi plate 740 is annular in configuration, and ispositioned within the valve body 703 closely adjacent the sliding valveplate 710. The cut-ofi plate 740 includes a plurality of cut-off ports741A and 741B which are positioned to selectively admit working fluidinto the staggered ports 705A and B from the interior of the valve body703. In the illustrated embodiment, atotal of six ports 741A and B arestaggered and radially spaced in the cut-off plate 740. Three of theports 741A are radially positioned for alignment with the outeradmission slots 712A and 714A in the valve plate 710. The remainingthree ports 741B are radially positioned for alignment with the inneradmission slots 7123 and 714B. The ports 741A and B may be circularapertures as shown in FIG. 12, or can be arcuate slots, as desired.

A generally cylindrical pressure plate 750 maintains the cut-ofi' plate740 in the proper position with respect to the valve plate 710. Thepressure plate 750 includes a central hub portion 751 and a peripheralflange por tion 752. A plurality of drive pins 753 are provided in theflange portion 752 to join the pressure plate 750 to the cut-ofi' plate740 so that the plates 740 and 750 can move axially with respect to eachother, but will rotate in unison. A compression spring 754 is positionedaround each pin to urge the cut-off plate 740 inwardly (to the left inFIG. 11) into continuous sliding contact with the rotating valve plate710. A cover plate 760 supports the hub portion 751 of the pressureplate 750 within a central bearing 761. An inlet port 762 is provided inthe cover plate 760 to allow the introduction of pressured working fluidinto the valve housing 703.

In accordance with this invention, the valve system 700 includes ashifting apparatus which permits the cut-off rate of the engine to bevaried by changing the,

position of the cut-off plate 740 with respect to ports 705 in the valvebody 703. In this regard, a manual shifting lever 770 is fixed to thehub portion 751 of the pressure plate 750. A compression spring 771biases the lever 770 upwardly toward a rachet type quadrant 772. A stop773 on the lever 770 is engageable with the quadrant 772 to selectivelyretain the lever in a plurality of positions within the arcuate range ofthe quad rant. By this arrangement, the lever 770 can be rotated betweentwo selected extremes to shift the position of the cut-off plate 740,and the cut-ofi ports 741A and B, rotationally with respect to the ports705A and 705B in the valve housing 703.

As described with respect to the engine 500 shown in FIGS. 8-9, thegeometry and positioning of the admission slots 712, 714, the valve bodyports 705A, B, and the cut-off plate 740 determine the timing andduration or cut-off of the admission of working fluid into the engine500A. In the preferred arrangement, the valve system 700 is designed topermit full admission (i.e., 100% cut off) of the working fluid intotherotor housing 520 as a maximum duration of fluid admission and about25 percent of the arm power stroke as a minimum admission duration(i.e., 25 percent out off). The full admission of working fluidfacilitates start-up of the engine 500A, and the 25 percent cutoffprovides a theoretical optimum utilizationof the energy in the workingfluid, such as superheated steam.

To allow for full admission, the valve system 700 is dimensioned sothat, in the illustrated embodiment, the effective length of theadmission slots 7112, 714 (the angle alpha), in combination with thewidth of the ports 7 05, produces admission for about 80 of rotorrotation. As described with respect to the engine 500, such anarrangement provides about five degrees advanced admission, to till thevarious ports with pressurized working fluid, and about 15 of overlap inthe operation of adjacent pairs of arms 540. To allow for a 25 percentcut off as a minimum duration of admission for the working fluid, thevalve system 700 is arranged to permit the shifting of the cut-off plate740 circumferentially with respect to the valve body 703 so that theeffective length of the admission slots 712, 714, and ports 705 arediminished to produce admission for about 20-25 of rotor-rotation. Acharge of working fluid will thereby flow. into the rotor housing 520through the admission slots 712, 714 fora duration equal to the fivedegrees advanced rotation of the rotor, plus about 25 percent of theinward stroke of the associated arm 540.

durationot admission of the working fluid from the in? terior of thevalve body 703 into the rotor housing 520, through the ports 705A, 7058,and 523. The location of the ports 705A and B control the admission ofworking fluid into the engine 500A under such conditions. Due to theselected arcuate length of the slots 7112 and 714, one of theset ofslots 712A, 7MB or 712B, 7MB will be positioned in alignment with a pairof diametrically opposed ports 705A, B and 741A, B, regardless of therotational positionof the valve plate 710. Hence, dead spots ordead-center conditions are eliminated from the engine 500A, and theengine will be selfstarting.

The valveplate 710 feeds a charge of working fluid into the rotorhousing 520 for operation against two diametrlc'ally opposed arms M30,as described in detail with respect to the engine 500. The resultingmovement of the rotor 550 and shaft 530A, in turn, drives the valveplate 710 in the same direction and at the same angular speed. Thevrotating plate 7110 sequentially exposes the aligned intake ports 705and cut-off ports 741 to the-workingfluid within the valve housing 703,and thereby feeds charges of working fluid into the rotor housing 520,for operation against pairs of arms 540 at timed intervals. Whenadjusted for full admission, the plate 710 admits a charge of workingfluid into each of the ports 705A and B for a period of approximately ofrotor rotation in advance of arm.

movement; an additional rotor rotation of approximately 60 degrees tocause inward movement of the associated arms 5; and a final rotorrotation of approximately to assure overlapping operation of adjacentthrough the inlet ports 523 for operation against a pair ofdiametrically opposed arms 540. Since the arcuate lengths of the slots712A, B and 714A, B are equal, the duration of the admission through theslots will be likewise equal.

To decrease the duration of admission of the working fluid into therotor housing 520, the cut-off plate 740 of the valve system 700 isrotated by the lever 770 in a direction opposite to the direction ofrotation of the "valve plate 710. As viewed in FIG. 12, the shaft 530Aand the valve plate 710 rotate in a counterclockwise direction duringthe operation of the engine 500A. Accordingly, the cut-ofl rate of theengine is adjusted by rotating the cut-ofi plate 740 in a clockwisedirection. As seen in FIG. 12, this adjustment positions the cut-offports 741A andMiB in advance of the inlet ports 705A and.705B in thestationary valve housing 703.

Hence, as the valve plate 710 rotatescounterclockwise, the admissionslots 7112 and 7114 become aligned with the cut-off ports 741A and 741Bbefore reaching the inlet ports 705A and B. Since the circumferentialpositions of the inlet ports 705A and B are fixed, the adjustment of thecut-off plate 740 in a clockwise direction does not aflect the timingfor the alignment of the admission slots 712 and 7M with'the ports 705Aand B. Thus, the valve system 700 operates to begin the admission ofcharges of working fluid into the rotor housing 520 at the same initialtime in the engine operating cycle under all cut-off adjustments.

The arrangement of the cut-off ports 7411A and Mil; in advance of thefixed ports 705A and B will cause the admission slots 712 and 7 M tobecome aligned with the cut-off ports 741 before reaching the ports 705.In the same regard, the rotating admission slots7i2, 714- will remainaligned with the fixed ports 705A, B after rotation beyond theassociated cut-off port 7411A, B.

As illustrated in FIG. 12, the fluid will flow into the rotor housing520 only as long as the associated cut-oft" port 7011A, B is alignedwithone of the admission slots 712A, B or 714A, B, and will be cut offwhen the admission slots rotate beyond the'cut-off ports 741A, B.

Thus, the clockwise rotation of the cutoff plate 740 advances thecut-off of the working fluid into the admission slots 7T2 and 7M, sothat the fluid operates I against a pair of arms 500 for a duration ofrotor rota-

1. In a rotary engine having a rotor joined to a power output shaft, aplurality of pivoted power arms spaced uniformly around the rotor andsequentially movable in a generally radial direction against the rotorthrough an inward power stroke from an outermost to an innermostposition to transmit a torque force to the rotor and shaft, andexpandable fluid chamber associated with the radially outward side ofeach arm, the improvement comprising a rotary slide valve system forsequentially directing charges of working fluid into said chambers todrive the arms inwardly through their power strokes, said valve systemcomprising: a manifold for a supply of pressurized working fluid; fluidintake port means for each chamber in communication with said manifold;a rotatable valve plate joined for rotation in timed relationship withsaid rotor and positioned adjacent said intake port means to block fluidcommunication between said intake port means and said manifold, saidvalve plate including admission aperture means sequentially alignablewith said intake port means as said plate rotates with said rotor andshaft, to connect said intake port means in fluid communication withsaid manifold, said admission aperture means in said plate having aselected arcuate length along an arc substantially concentric with saidrotor to direct charges of working fluid from said manifold sequentiallyinto said chambers through said intake port means for a selected degreeof rotation of said rotor so that said charges sequentially drive saidarms through said inward power strokes.
 2. A vAlve system in accordancewith claim 1 wherein said arcuate length of said admission aperturemeans is selected to connect adjacent intake port means simultaneouslyin fluid communication with said manifold for a selected degree ofrotation of said plate, to overlap the sequential admission of chargesof working fluid into the chambers of adjacent arms and thereby overlapthe inward power strokes of adjacent arms for a selected degree of rotorrotation.
 3. A valve system in accordance with claim 1 includingadjustable fluid cut-off means in fluid communication with said manifoldand shiftable from an opened position, permitting fluid to flow fromsaid manifold into said admission aperture means, and a closed positioncutting off the flow of fluid from said manifold into said intake portmeans for a selected degree of rotation of said rotor.
 4. A valve systemin accordance with claim 1 including valve seats associated with each ofsaid intake ports and slideably engaged with said rotatable valve plateto maintain a substantially fluid-tight seal between said plate and saidintake ports during the operation of said engine.
 5. In a rotary enginehaving a rotor joined to a power output shaft, a plurality of pivotedpower arms spaced uniformly around the rotor and sequentially movableagainst the rotor through an inward power stroke from an outermost to aninnermost position to transmit a torque force to the rotor and shaft,and an expandable fluid chamber associated with each arm, theimprovement comprising a rotary slide valve system for sequentiallydirecting charges of working fluid into said chambers to drive the armsthrough their power strokes, said valve system comprising: a manifoldfor a supply of pressurized working fluid; fluid intake ports for eachchamber in communication with said manifold; a rotatable valve platejoined for rotation in timed relationship with said rotor and shaft andpositioned adjacent said intake ports to block fluid communicationbetween said intake ports and manifold, said valve plate includingadmission ports alignable with each intake port as said plate rotates tothereby connect said intake ports with said manifold, with saidadmission ports being arranged on said plate in radially staggeredrelationship with respect to said shaft so that adjacent admission portscommunicate with said manifold at different radial locations on saidplate; and an adjustable cut-off plate positioned adjacent said valveplate and operative to adjust the flow of fluid from said manifold intosaid intake ports by shifting circumferentially with respect to saidintake ports, said cut-off plate including a cut-off port positioned foraxial alignment with each admission port on said rotating valve plateand radially staggered around said cut-off plate; whereby said rotatingvalve plate directs charges of working fluid from said manifold intosaid chambers sequentially through said admission and intake ports for aselected degree of rotation of said rotor and shaft, to drive the armsthrough their inward power strokes, and said cut-off plate is shiftablewith respect to said intake ports to adjust the duration of admission offluid charges from said manifold into said engine chambers.
 6. In arotary engine having a symmetrical double-lobed rotor joined to a poweroutput shaft, a plurality of pivoted power arms spaced uniformly aroundthe rotor and movable against the rotor through an inward power stroketo transmit a torque force to the rotor and shaft, and an expandablefluid chamber associated with each arm, a valve system for directingcharges of working fluid sequentially into said engine chambers so thatthe power strokes of pairs of opposed arms coincide, said valve systemcomprising: a manifold for receiving a supply of pressurized workingfluid; a plurality of intake ports uniformly spaced around said manifoldat a selected radial position with respect to said shaft and extendinginto fluid communicAtion with each engine chamber; a rotatable valveplate joined for rotation in timed relationship with said rotor andshaft and positioned adjacent said intake ports to block fluidcommunication between said intake ports and said manifold, said valveplate including at least a pair of concentric admission apertures havingsubstantially the same arcuate length arranged in diametrically opposedrelationship and positioned for alignment with said intake ports toplace said intake ports in fluid communication with said manifold andthereby admit working fluid simultaneously into the engine chambers ofan opposed pair of arms as said valve plate rotates to align saidapertures with opposed intake ports.
 7. In a rotary engine having asymmetrical double-lobed rotor joined to a power output shaft, aplurality of pivoted power arms spaced uniformly around the rotor andmovable against the rotor through an inward power stroke to transmit atorque force to the rotor and shaft, and an expandable fluid chamberassociated with each arm, a valve system for directing charges ofworking fluid sequentially into said engine chambers so that the powerstrokes of pairs of opposed arms coincide, said valve system comprising:a manifold for receiving a supply of pressurized working fluid; aplurality of intake ports uniformly spaced around said manifold andextending into fluid communication with each engine chamber, with theportion of said intake ports communicating with the manifold beingarranged in a staggered relationship so that adjacent sets of intakeports communicate with said manifold at different radial positions withrespect to said output shaft, a rotatable valve plate joined forrotation in timed relationship with said rotor and shaft and positionedadjacent said intake ports to block fluid communication between saidintake ports and said manifold, said plate including a pair ofconcentric and diametrically opposed admission slots in axial alignmentwith each of said staggered sets of intake ports, said admission slotshaving substantially the same arcuate length and being operative toplace diametrically opposed intake ports in fluid communication withsaid manifold and thereby admit working fluid charges simultaneouslyinto the engine chambers of a pair of opposed arms as said valve platerotates to align said apertures with said opposed intake ports; and anadjustable cut-off plate positioned adjacent said valve plate andoperative to cut off the flow of fluid from said manifold into saidintake ports, said cut-off plate including a plurality of cut-off portsradially staggered around said cut-off plate and positioned for axialalignment with said admission slots on said rotating valve plate, saidcut-off plate further being shiftable circumferentially with respect tosaid intake ports to adjust the duration of admission of fluid chargesfrom said manifold into said engine chambers through said intake portsand admission slots; whereby said rotating valve plate directs chargesof working fluid from said manifold simultaneously into the chambersassociated with a pair of opposed arms and said cut-off plate adjust theduration of admission of said fluid charges for a selected degree ofrotation of said rotor and shaft.